The kinetic theory of matter states that matter is made up of tiny particles such as atoms, molecules, and ions. These particles are continually moving, so they possess kinetic energy.
b. Outline three natural phenomena that support it.
Phenomena supporting kinetic energy
i. Diffusion
ii. Osmosis
iii. Brownian movement
Diffusion: This is the movement of molecules of a substance from a region of higher concentration to that of lower concentration. For instance, if a perfume is sprayed in corner of a room, its molecules will diffuse to all parts of the room within a short time.
Osmosis: This is the movement of water molecules or other solvents from a region of lower concentration to a region of higher concentration through a semi-permeable membrane.
Brownian Movement: This is the zig-zag, irregular motion exhibited by minute particles of matter when suspended in a fluid.
Theory Question 2
2. (a) Give three differences between Solid and Liquid
Solid
Liquid
(1) Has a fixed shape
Has no fixed shape
(2) Movement is restricted in solids
Movement is less restricted in liquids
(3) Solids are very dense
Liquids are less dense as compared to solids
(b) Which state of Matter contains particles that are:
(i) Readily compressed – Gaseous state
(ii) Held firmly by some forces of Cohesion – Solid-state
(iii) Involved in rapid motion – Gaseous state
Theory Question 3
3. (a) Explain how impurity in a substance affects
(i) Melting point – When a substance e.g. solid contains an impurity, it lowers the melting point of the solid.
(ii) Boiling point – When a substance contains an impurity, it raises the boiling point of the pure liquid. The boiling point of a liquid is sharp.
(b) State one Similarity and two differences between Boiling and Evaporation
i. Similarity – Boiling, and evaporation are both states of matter
ii. Differences
Boiling
Evaporation
(i)
Bubbles are seen
Bubbles are not seen
(ii)
Occurs throughout the liquid
Occurs at the surface of the liquid
(iii)
Causes heating and an increase in the entropy of the system
Causes cooling and a decrease in the entropy of the system
Theory Question 4
4. Write short notes on the following
(a) Latent heat of Vaporisation
Answer – This is the energy absorbed by a liquid as it turns into gas to overcome the cohesive force during boiling.
(b) Tyndal Effect
Answer – This is the scattering of light as a light beam passes through a colloid. The individual suspension particles scatter and reflect light, making the beam visible.
(c) Dialysis
Answer – This is the process whereby crystalloids in a true solution pass through a permeable membrane.
(d) Brownian Motion
Answer – This is the zig-zag, irregular motion exhibited by minute particles of matter when suspended in a fluid.
Theory Question 5
5. (a) Evaporation causes Cooling. Explain
Answer – This occurs as a result of the particles of liquid and the energy in the surrounding i.e. particles of liquid absorb energy from the surrounding or environment to regain the energy lost during evaporation.
(b)
The above is a diagrammatic representation of the changes in the states of Matter (i) Name all the processes involved from 1 to 6
Please note:
This action will also remove this member from your connections and send a report to the site admin.
Please allow a few minutes for this process to complete.
